from django_redis import get_redis_connection
from rest_framework import serializers
import re
from celery_tasks.email.tasks import send_active_email
from goods.models import SKU
from users import constants

from .models import User, Address
from rest_framework_jwt.settings import api_settings

class CreateUserSerializer(serializers.ModelSerializer):
    """创建用户的序列化器"""
    password2 = serializers.CharField(label='确认密码',write_only=True)
    sms_code = serializers.CharField(label='短信验证码',write_only=True)
    allow = serializers.CharField(label='同意协议',write_only=True)
    token = serializers.CharField(label='登录状态token',read_only=True) # 增加token字段

    class Meta:
        model = User
        fields = ("id", 'username', 'password', 'password2', 'sms_code', 'mobile', 'allow', 'token')
        extra_kwargs = {
            'username':{
                'min_length':5,
                'max_length':20,
                'error_messages':{
                    'min_length':'仅允许5-20个字符的用户名',
                    'max_length':'仅允许5-20个字符的用户名'
                }
            },
            'password':{
                'write_only':True,
                'min_length':8,
                'max_length':20,
                'error_messages':{
                    'min_length':'仅允许8-20个字符的密码',
                    'max_length':'仅允许8-20个字符的密码'
                }
            }
        }

    def validate_mobile(self,value):
        """验证手机号码"""
        if not re.match(r'^1[3-9]\d{9}$',value):
            raise serializers.ValidationError('手机号格式错误')
        return value

    def validate_allow(self,value):
        """验证用户是否同意协议"""
        if value != 'true':
            raise serializers.ValidationError('请同意用户协议')
        return value


    def validate(self, data):
        """判断两次密码一致"""
        if data['password'] != data['password2']:
            raise serializers.ValidationError('两次密码不一致')

        # 判断短信验证码
        redis_conn = get_redis_connection('verify_codes')
        mobile = data['mobile']
        real_sms_code = redis_conn.get('sms_%s' % mobile)
        if real_sms_code is None:
            raise serializers.ValidationError('无效的短信验证码')

        if data['sms_code'] != real_sms_code.decode():
            raise serializers.ValidationError('验证码错误')

        return data


    def create(self, validated_data):
        """
        重写保存方法，增加密码加密
        """
        # 移除数据库模型类中不存在的属性
        del validated_data['password2']
        del validated_data['sms_code']
        del validated_data['allow']

        # user = User.objects.create(username=xxx, password=xx)
        # user = User.objects.create(**validated_data)

        user = super().create(validated_data)

        user.set_password(validated_data['password'])
        user.save()

        # 签发ｊｗｔ　token
        jwt_payload_handler = api_settings.JWT_PAYLOAD_HANDLER
        jwt_encode_handler = api_settings.JWT_ENCODE_HANDLER

        payload = jwt_payload_handler(user)
        token = jwt_encode_handler(payload)

        user.token = token

        return user


class UserDetailSerializer(serializers.ModelSerializer):
    """用户详细信息序列化器"""
    class Meta:
        model = User
        fields = ('id', 'username', 'mobile', 'email','email_active')


class EmailSerializer(serializers.ModelSerializer):
    """邮箱序列化器"""
    class Meta:
        model = User
        fields = ('id', 'email')
        extra_kwargs = {
            'email':{
                'required':True
            }
        }

    def update(self, instance, validated_data):
        """视图传过来的user对象"""

        email = validated_data['email']

        instance.email = email
        instance.save()

        # 生成激活链接
        url = instance.generate_verify_email_url()

        # 发送邮件
        send_active_email.delay(email, url)

        return instance


class UserAddressSerializer(serializers.ModelSerializer):
    """用户地址序列化器"""
    province = serializers.StringRelatedField(read_only=True)
    city = serializers.StringRelatedField(read_only=True)
    district = serializers.StringRelatedField(read_only=True)
    province_id = serializers.IntegerField(label="省ID", required=True)
    city_id = serializers.IntegerField(label="市ID", required=True)
    district_id = serializers.IntegerField(label="区ID", required=True)

    class Meta:
        model = Address
        exclude = ('user', 'is_deleted', 'create_time', 'update_time')

    def validate_mobile(self, value):
        """验证手机号"""
        if not re.match(r'^1[1-9]\d{9}$', value):
            raise serializers.ValidationError('手机号格式错误')
        return value

    def create(self, validated_data):
        "保存"
        validated_data['user'] = self.context['request'].user
        return super().create(validated_data)


class AddressTitleSerializer(serializers.ModelSerializer):
    """地址标题"""
    class Meta:
        model = Address
        fields = ('title',)


class AddUserBrowsingHistorySerializer(serializers.Serializer):
    """添加用户浏览历史序列化器"""
    sku_id = serializers.IntegerField(label="商品SKU编号", min_value=1)
    def validate_sku_id(self, value):
        """检验sku_id是否存在"""
        try:
            SKU.objects.get(id=value)
        except SKU.DoesNotExist:
            raise serializers.ValidationError("该商品不存在")
        return value

    def create(self, validated_data):
        """保存"""
        user = self.context["request"].user
        sku_id = validated_data["sku_id"]


        redis_conn = get_redis_connection("history")
        pl = redis_conn.pipeline()
        redis_key = "history_%s" % user.id


        # 移除已经存在的本地商品浏览记录
        pl.lrem(redis_key, 0, sku_id)
        # 添加新的浏览记录
        pl.lpush(redis_key, sku_id)

        # 只保存最多五条记录
        pl.ltrim(redis_key, 0, constants.USER_BROWSE_HISTORY_MAX_LIMIT-1)
        pl.execute()

        return validated_data


